Field of the Invention
The embodiments herein relate to testing of integrated circuits and, more particularly, to the calibration of temperature sensors included in integrated circuits.
Description of the Related Art
The performance of high-end integrated circuits (ICs), such as, for example, microprocessors, has increased over the years and continues to increase when looking at IC designs for the future. Generally speaking, the performance boost of microprocessors may be associated with higher clock frequencies (i.e., shorter clock periods) allowing more instructions to be executed in a given period of time and smaller manufacturing technologies that allow more complex circuits to be designed into a given area of a chip (i.e., higher density circuits), allowing for more functionality. These increases in processor frequency and circuit density, however, may include increases in power consumption and thus, may increase chip temperature and temperature variations inside the chip.
A microprocessor operating at a high temperature with temperature variations across the chip may experience various issues, such as, for example, performance degradation, leakage power increase, reduced reliability, function failures, etc. Thermal considerations, therefore, may need to be properly addressed during microprocessor chip design. One method to obtain temperature information may be to place a respective temperature sensing circuit at several locations on the chip. Calibration of each temperature sensing circuit may be performed to improve an accuracy of each circuit's temperature measurements.